Portable handheld drilling apparatus of this kind have the disadvantage that unexpected torque increases can occur when the auger encounters resistances in the drill hole such as stones, roots or the like. These unexpected torque increases can lead to a sudden reduction of rpm of the auger or even cause the auger to become blocked or jammed. The braking torque occurring thereby must be taken up by the operator via the guide handle and this can lead to a considerable safety risk since the operator can lose his hold on the apparatus and be injured thereby.